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FURNACE Filed Deo. 13 1920 5 Sheets-Sheet l ww. A

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' 5 sheets-2'sheety 2Vv M. c. STEESE FURNACE Filed. Dec. 15 -1920FURNACE Filed Dec. 15 1920 f' 5 sheets-sheet 5 will NOV., 26, 192% 'y M,Y; s TEEsE 3,737,392v

FURNACE l Filed Dec. 15 1920 5 Sheets-Sheet 4 Nov. 26, 1929, M. c..eL-'rEEsE FURNACE Filed Dec. 1:5 1920 5.. Sheets-Sheet 5 Patented Nov.26, 1929 llllAIEtCUS C. STEESE, OF HAMBURG, NEW YORK oF'Fi FURNACEApplication filed December 13, 1920. Serial No'. 430,194.

This invention relates to open hearth furnaces, and more particularly tothe fluid passageways and the control of fiuidspassing therethrough, andalso to means for'obtaining more efficient combustion of various fuels.

The presentconstruction of an open hearth furnace consists of the usualhearth, combustion chamber and port block arrangement, which is standardfor most all types of open hearth furnaces 4 A furnace using producergashas in addition usually one uptake for gas on each end and its gas port,and two uptakesv forair on cach end and air ports. The lower ends ofthese uptakes terminate, respectively, in a gas slag pocket and air slagpocket on each end, which are in turn connected to gas checkers andaircheckers, respectively which are in turn connected vto the stack throughgas and air reversing valves, both ends of the furnace being the same.

Generally, in furnaces usingiiatural gas or coke oven gas and tar,another construction is resorted to in-connection' with the uptakes, inwhich the furnace is constructed with one large uptake extending acrosseach end of the furnace, this terminating at the lower end in one slagpocket, which in turn is connected with the air regenerator, which inturn isA connected to the/stack' through a reversing valve. This secondclass of furnaces is sometimes operated by usingthe standard producergas furnace and cutting the slag pocket walls out bet-ween the slagpockets, making one large chamber, and using both the gas and airregenerators on either end. v Y g op A third type of furnace recentlydeveloped is similar in construction to a producer gas furnace with theexception that dampers are placed in the four air uptakes witlroperatingmechanism for closing and opemng said dampers, and the slag pockets areconnected by cutting through the walls.

All these types of furnaces are built especially for their respectivefuels,.and itis a matter of considerable time and expense to change fromone fuel to another, the change involving. cooling off the furnace andtearing down brickwork, and rebuilding and heatvgas or tar furnaceinvolving the large unit fuels.

ing up the furnace again. Owing to the close connection also between theslag pocket and the checker chambers or regenerators, the function ofthe slag pocketvbeing to collect the heaviest particles of materialcom/ing down the uptakes so that the gas in passing to the checkerchambers is as clean as possible, a great deal of dirt collects on topof the checker chambers and decreases the life thereof by eitherclogging up or depositing a coating on top. There would be advantagegained in this respect if it were possible to provide a settling chamberbetween the slag pocketand checker or regenerator chamber, lWhere thegases would still drop more of the suspended matter contained therein,and this would materially lengthen the life of the checkers three orfour times. I, In the first type of furnace, namely, a producerv gasfurnace, sometimes it becomes /ad visable to introduce a tar burner or agas burner within the gas port. This requires considerable time andexpense ,and in this type of furnace it is further quite a problem toarrange the uptakes at either lend of the furnace, to provide sufficientarea ,for the outgoing g'ases and waste products, and the life of thefurnace is quite often 'terminated by the burning through of thedivision walls: There also being' two slag pockets 'of'necessarily smallcomparative size, one/pr the other will often iill up rapidly, whichagain terminates the life of the furnace. Accordingly there is greatadvantage in constructing a furnace of the second type, namely, astraight uptake and the large single slag pocket and the singlelcheckerchamber; but this type of furnace would be useless for the burning ofproducer gas. .It is more or less successfully used for tar, coke .ovengas and powdered Qne object, therefore, of my present invention is Atoprovide an open hearth furnace construction in which all fuels may beefficiently burned interchangeably Without change in Vconstruction 'oroperation.

Another object is to provide a more eilicient combustion than ispossible at present in the large uptake type of furnace describedhereinabove when using Coke oven gas, tar

or powdered coal.

Another object is to automatically control the total quantity of air inaccordance with the supply of fuel.

Another object is to provide for an intimate mixture of fuel and air anda partial combustion of same prior to entering the combustion chamber.

Another object is to accomplish'these functions with no additionalapparatus, and, as a matter of fact, with less apparatus than isnecessary on the present producer gas furnace.

These .andother objects are accomplished by means of the arrangementsdisclosed on the accompanying sheets of drawings, in which- Figure 1 isa fragmentary longitudinal sectional vieW lof an open hearth furnaceembodying my invention; y

Figure 2 is a transverse sectional view taken in the plane of line 2-2of Figure 1;

Figure 3 is a'fragmentary longitudinal sectional view of an open hearthfurnace embodying a modification of my'invention;

Figure 4 is a fragmentary sectional view taken in the plane of line 4-4of Figure 3;

Figure 5 is a transverse sectional view of the open hearth furnace takenin the plane of line 55 of Figure 3; and, i

Figure 6 is a plan sectional view taken in the plane of line 6-6 ofFigure 5. 1

The various novel features of my invention will be apparent from thefollowing de-l scription and drawings and will be particularly pointedout in the appended claims.

Referring first to Figures l and 2 of thev drawings, it will be notedthat I lhave shown.

an open hearth furnace having a hearth 10 upon which a bath 11issupported, there being two ports A12 and 13 leading to the combustionchamber .14. These ports 12 .and 13 are in open communication with onelarge uptake 15 whichcommunicates with a central uptake. 16, which inthe regular open hearth furnace is the' gas uptake, and with two otheruptakes 17. It will be understood that these uptakes 16 and 17 areconnected with their respective slag pockets 18 and 19, which areconnected with theusual checker or regenerator chambers. p Transverselyof, and preferably in the middle of, the large uptakey 15, I provide abaille or air trap 20,

vwhich preferably is semi-circular in section.

This baffle extends through the end wall 21 of the furnace, through theuptake 15 and into a receiving openmg in -the port block 22. Mountedwithin the semi-circular baliie 20 and extending through the end 4wall21 of the open hearth is a fuel burner 23, which may be of any suitabletype and which includes -a conduit 24 for the supply of various fuels,

14, the velocity is retardedbelow the rate of flame propagation,whereupon combustion takes place completely and at a very high rate.This complete combustion is assisted by an auxiliary or excess supply ofair through the port 13, such auxiliary air also directing the flamingAcombustible mixture onto the bath, and guiding the direction ofmovement through the combustion chamber. The air which'passes throughtheport 13 is the excess of the air not induced by the flow yof fuelunderpressure through port 12, and

this excess amount of air is under the control of the furnace operatorand regulated by a valve for admitting air through the rel generator orchecker chambers. The total amount of air entering the furnace throughthe uptake 15 is a result of the thermal head or temperature in theuptake and is controlled by a val-ve'admitting airto the bottom of theregenerators. This air in flowing upwardly, due toits'natural head, isdivided by the inducing action of the fuel under pressure, part mixingwith the fuel and entering the furnacethrough the opening 12 and theremainder passing on.either side of the baille 20, reference being hadarticularly to Figure 2, and entering the urnace through the air port*13. With a fixe-d amount of air iowing up the air uptake 15, and withthe control of the injection of air.. through port 12, more or less aircan be induced through port 12, and if all of the air were inducedthrough ort 12, none wouldpass on either side of the 4 afle 20 and enterthe furnace `through port 13. Therefore, it is possible by means of theair valve 35-below the regenerator and the injection action to controlthe amount of 'air entering through port 12 and the amount of airentering through port 13`within wide limits and easily under the controlof the operator, A

AIt is desirable to have a certain quantity of air enter the furnacethrough port 13 and that amount would bel indicated by a certain smallpressure evidenced at the rear of port 13. By means of a suitablediaphragm construction, which would operate electric contacts, a smallmotor would raise and lower the air valve, which permits air to enterthe bottom of the regenerator, the amount of air flowing up uptakes 15would be automatically controlled as the operator would vary the flow offuel through burner 23, which in turn automatically causes more or lessair to be induced from uptake 15 through port 12 into combustion chamber14.

One form of automatic control referred to hereinabove may take the formof a delicate pressure member, such as swinging-damper 28, whichoperates within a pipe 29 in open communication with the upper end ofuptake 15. A contact 30 at the upper end ofthis damper may electricallyengage contacts 31 and 32, which are in the circuitof the propellingmotor 33 for actuating any suitable mechanism 34 for raising andloweringr the airvalve 35, which controls the flow of air to theregenerators, from which said air passes through slag pockets 18 and 19,uptakes 16 and 17, uptake 15, and into the combustion chamber throughports 12 and13, as hereinabove described. For example, if the pressurein the uptake 15 is above a predetermined value, as set by the furnaceoperator, the damper will move outwardly and'contact 30 engage withcontact 31 for moving the valve 35 toward a closed position. On theother hand, if the pressure at'the upper end of up take 15 is below saidcertain predetermined value, the damper 28 will move inwardly so thatcontact 30 will engage contact 32 lfor causing the air valve 35 to beopened a given amount, whereupon additional air will be supplied to theuptake 15.

Referring now to Figures 3 to 6, inclusive, attention is first directedto the fact that instead of providing a plurality of slag pockets, asshown in Figures 1 and 2, a single slag pocket 36 is provided, which isin 'open communication with one large uptake 37, which extends the fullwidth, or the greater/part thereof, of the furnace. This furnace isprovided with the usual hearth 38 on which the bath 39 is supported,there being an air intake port 40 connecting the upper end of y theuptake 37 with the comb-ustion chamber 41. Introduced across uptake 37is one or more baffles or air trapsA 42, .which extend through the endwall 43 of the furnace and across uptake 37 and extend into openings inthe port block 44. These baliies 42 preferably are semi-circular insection with the open portion-downward. The inner or active end of'eachof the bali'les is provided with a throat 45, the function of which willbe more fully described hereinafter. Mounted within this baffle andextending through the end wall and partially across the air uptake 37 isa fuel burner 46, the active end of which terminates somewhere withinthe up-` take 37, and arranged so as to be adjustable of its length andtransversely within the uptake. The burner is movably supported on pipes60 and the burner is permitted to move back and forth as a result of theflexible member G1 located at the outer end of the burner in the fuelsupply line. The center line of thc jet of the burner coincides veryclosely with the center line of the throat 45. The fuel is supplied tothis burner under pressure suitable to perform the necessary function ofinducing sufficient air through the throat 45 from uptake 37 tocombustion cham ber 41 to provide an intimate mixing of fuel and air inthroat 45 and partial combustion therein and this mixture up'on enteringthe combustion chamber 41, where the velocity of the mixture falls belowthe rate of flame propagation, results in a rapid combustion of thismixture whi'cliis completed by the cess air entering through port 40also directs the flame upon the bath and across the furnace. The amountof air rising up uptake 37 is a function'of the opening of the controlvalve 47 and the thermal head or temperature in the uptake, and thisamount is under the controlJ of the furnace operator. Upon reaching theplane of the baffies suflicient air to mix with" the fuel in the`lthroat 45 is induced into and through this throat by action of the fuelunder pressure. The remainder of the air passes around these baffles andenters the furnace through port 40. This phase of thc invention consistsin utilizing the induction action of a jet of fuel under pressure forseparating the upward'flow of air in uptake' 37, the required amount ofwhich is forced through the throat 45 by the inductive action of thefuel jet, wheredan intimate mixture of the fuel and air is obtained. There mainder of the air flowing through uptake 37 enters the furnacethrough port 40 to complete combustion. In other words, the injectionact-ion is not utilized to draw the-air up uptake 37 Abut is utilizedfor directing the air after it has reached the baffles in the uptake.The air flows up through the uptake 37 as the result of the thermal heador the temperature within said uptake, and the entire energy of the fueljet is utilized in forming the intimate mixture and inducing the air Iwish to emphasize the fact that the inducingvaction of the burner isutilized only to'v l induce through thethroat and mix with the fuel, thenecessary amount of'air to form a combustible mixture and cause apartial combustion within the port, the complete combustion taking placeafter the induced mixture has passed into the combustion chamber and metthe air through the air port 40. The difference in pressure on eitherside of the port block, that is,c in the combustion chamber 41 on oneside and the air uptake 37 on the other,

is slight, and as the volume of air capable of rising up the uptake 37is much in excess of the requirements and the amount rising is under thecontrol of the operator, and the amount induced through the throat iscon! stant for-each fuel amount and. burner setting,

the amount of air which passes by the baffles and thence to the furnaceis directly under the full control of the furnace operator. Re-

gardless of how much air is passing up the uptake 37, the Huid passingthrough the throat and the energy necessary to effect such passage isconstant for each setting of fuel burner. The inducedA air isproportionate to the fuel supply.

In reversing this furnace, working on producer gas, there being no gascheckers and chambers necessary, there is no lossof gas .contained inthem which is wasted to the stack. This amounts to alsaving of 3 to 7%of fuel.l

In connection with the air intake and the discharge of the products ofcombustion, the furnace is provided preferably with a single checker orre enerator chamber 50, a settling chamber 51, fiile slag pocket 36 anduptake 37. In connection with the passage of air, air is drawn in pastvalve 47 through air. checker chamber 50, where the air is heated,whereupon the air passes through settling` chamber 51, slag ocket 36 andup through air uptake 37 in t e manner hereinabove described. Whenthefurnace is reversed, the products of combustion pass downthe uptake37 through slag pocket 36 where the heaviest particles are deposited andthen into settling chamber 51,

where less heavy particles are deposited priorl to the products ofcombustion continuing on into the checker chamber 50. In this manner thecheckers are prevented from being clogged by relativel heavy materialcarried with the products o. combustion. Upon leaving the air checkers,the products of combustion pass Y outwardly through a flue 52 leading.to a reshown.

versing valve, not shown, and the stack, not

While I have shown myinvention as applied to an open hearth furnace, itwill be understood that it may be applied to 4furnaces other than openhearth furnaces. For instance, it may be used in connection with largereheating furnaces in steel mill practice for heating billets, slabs andbars preparatory to being rerolled.

There may be various modifications of the invention, and it is myintention to cover all such modifications which do not involve adeparture from the spirit and scope of the invention as set forth in thefollowing claims.

I claim:

l. In an open hearth furnace, an air uptake, and a fuel burnerad'ustably mounted within said uptake and Inova le with respect to theport in said port bloc-k in accordance with varying conditions.

2. In an open hearth furnace, a port block, a bafHe located between anend wall of the furnace and the port block, and a fuel burner associatedwith said baffle and movable with respect to the port in said port blockto meet the varying conditions of pressures and kinds of fuel used.

3. In an open hearth furnace, a port block,

lan uptake, means for supplying fuel under pressure to the port in saidblock for inducing a supply of air from said uptake whereby acombustible mixture of air and fuel and a preliminary combustion takesplace Within said port, further air from said uptake mixing with thecombustible mixture eyond the port for completing combustionof thecombustible mixture within the combustion chamber. f

4. In an open hearth furnace, a port block,

an uptake, means for'supplying fuel under pressure to the port in saidblock for inducA ing a supply of air from said uptake whereby acombustible mixture of air and fue] and va vpreliminary combustion takesplace within said port, and means whereby further air from said uptakemixes with the combus tible mixture beyond the port for completingcombustion of the combustible mixture within the 'combustion chamber,said 'additional vair directing the fiame ontothe bath and through thecombustion chamber.

5L Ian an open hearth furnace, a combustion chamber, an uptake foraccommodating large Volume of fiow of productsof combustion,

means for supplying fuel under pressure for flowing through said uptake.

7.In an open hearth furnace, an uptake permitting a large inflow of airinto the combustion chamber and a large outflow'of prod-` ucts ofcombustion therefrom, means for supplying fuel under pressure forinducing a given amount of air from said uptake under given conditionsfor forming a combustible mixture regardless of the quantity of air aport block,

v combustible -mixture flowing through said uptake, and a regulatingvalve for controlling the supply of air passing up the uptake.

8. In an open hearth furnace, an uptake. for the passage of air to thecombustion chamber and for the passage of products of combustiontherefrom, and means for auto-` matically controlling the pressure ofthe air in the Aupper part of said air uptake. A 9. In an open hearthfurnace, a combustion chamber, an uptake through Which air may pass tosaid combustion chamber and through which products of combustion maypass from said combustion chamber, meansv for supplying fuel underpressure for inducing a given amount of lair from said uptaketo form aregardless of the amount ofair passing through said uptake,

and means for automatically controlling the volume of air passingthrough said uptake.

l0. In an open hearth furnace, a combust tion chamber, a large volumeuptake through Whichair flows and through Whichwaste gasespass, andmeans for supplying fuel u nder pressure for' dividing the supply. ofair passing up the uptake and inducing a portion thereof to form acombustible mixture prior to passing into the combustion chambenthedivision of air being made regardless of the area provided for thepassage of excess air,

the large area provided for excess of air per-j mitting of free passageof Waste-gases from the furnace to the stack.

11. A furnace provided at each end With air and fu'el flues, a separatecontinuously open discharge at each Vend operative to conduct productsof combustion from the fuinace onfthe outgoing and While admittingsubstantially no air into the furnace on the incoming end.

Signed at Chicago, Illinois, this 23rd day of November, 1920.

MARCUS C. STEESE.r l

